Magic Mountain was a theme park in Glenelg, a beachside suburb of Adelaide, South Australia. It opened in December 1982 and closed on 18 July 2004.
Magic Mountain was popular among the young and "young at heart", but had also been criticised for its design, which was likened to a "giant dog dropping". It was demolished amid controversy late in 2004 as part of the final stage of the Holdfast Shores development and replaced by The Beachouse in 2006.
Magic Mountain was popular more with locals than tourists, and especially with younger people. The main attraction of Magic Mountain were its four water slides (the largest in the southern hemisphere at the time), particularly during the hot Adelaide summer. Other attractions included the historic carousel (which has been preserved), mini-golf, bumper boats, dodgem cars and sky cycles, pinball machines and video arcade games.
 Closure and demolition
Demolition of Magic Mountain was part of the second stage of the Holdfast Shores development, and was required in order to maintain the stipulated amount of open space. The plan, signed in 1997, included a profit-sharing agreement between the state government and the Holdfast Shores consortium, and a separate agreement concerning public infrastructure with the local government (the City of Holdfast Bay).
Stage 1 saw the construction of the marina, the Marina Pier and two apartment blocks. The second stage was construction of the Pier Hotel. Agreements changed before Stage 2 began. The state government withdrew from the now-considered risky hotel development and sold the land to the consortium. The plan also changed, with the separation of the hotel from the Platinum Apartments – the new plan became known as Stage 2B.
Meanwhile, a public-opinion survey in the lead-up to the May 2003 local government elections caused the council to rethink its support of the new plan. Their new-found opposition to the proposed beachfront high-rise apartments focused on Magic Mountain as the one parcel of land within the project that was under their control.
The council's campaign was ultimately unsuccessful and the development received Government approval in early 2004. Magic Mountain closed for the last time on 18 July 2004 and was demolished soon after. The new development included construction of The Beachouse, replacing Magic Mountain, which opened on 1 July 2006.